Equalizer rod



April 1932- J. A. L.MOLLYER 1,853,569

'EQUALIZER ROD Filed April 6, 1929 //l III II I/ I INVENTOR BY MFMATTORNEY Patented Apr. 12, 1932 UNITED STATES PATENT OFFICE.

AcoB A. L. uiinnna, on NEW YORK, N. Y.

EQUALIZER BOD Application filed April 6, 1929. Serial no. ss,225.-

, 5 paper, waxed paper and similar products.

Machines have been developed for this purpose which apply the coatingmaterial to paper by passing the paper under tension over a roller whichapplies the coating material to one side of the paper after which thecoated face of the paper is passed over a rod. or bar, termed anequalizer rod, for

spreading the material over the surface of the paper and removing excessmaterial therefrom. One type of machine emplo ed for this purpose isillustrated and descri ed in the patent to Mayer, No. 1,043,021, datedOctober 29, 1912.

The equalizer rod shown and described in that patent is in the form of along rod having convolutions on its face. These convolutions are formedby applying closely wound wire of small diameter thereto or by cuttingvery fine threads in the surface of the rod. The paper being coatedpasses over the equalizer rod so that the active or bearing portion ofthe wire or threads are soon worn down. This causes the equalizer rod toscrape off more of the dope or coating material with the result that thelayer of coating material applied to the paper becomesthinner as thewire or threads are worn down to a greater degree. As a result of thiswearing away 5 of the convolutions or the equalizer rod the coatingbecomes relatively thinner and consequently the product obtained fromthe machine is not uni-form. V

The principal object-of thepresent inven- 40 tion is to produce aproduct coated more uniformly than heretofore been thought pos- V sible.

A further object of the invention is' to improve the construction ofequalizer rods em- 5 ployed for the purpose described and to increasethe life and service obtained therefrom.

These and other important objects and features ofthe invention will morefully appear from the followingdescription of the preferred form of theinvention illustrated in the drawings.

In'the 'drawings- Figure 1 is a diagrammatic view of a por- I tion of amachine embodying the present in-. vention;

Figure 2 illustrates a portion of the equalizer rod employed in theconstruction shown in Figure 1; and

Figure is a sectional view of the form of equalizer rodillustrated inFigure 2.

The form of the invention illustrated in the drawings is applied to amachine such as is shown in said patent to Mayer, No. 1,043,021, and forconvenience of reference the same characters are used herein as are usedin the patent.

The material 2 to which the coating is to be appliedis passed oversmoothing and tensioning members 19,20, 21 and 22. The members 19 and 22are provided with square edges which smooth out any wrinkles which maybe in the paper before it passes over the coating roller 33. Thecoatingroller is partially immersed in the coating material contained inthe vessel 25. The coating material is carried on the surface'of theroller 33 as it rotates in the direction of the arrow and is thusapplied to the under-surface of the paper.- The coating material appliedto the paper adheres thereto and is smoothed out by the equalizer rod 56over which the paper passes immediately after the coating material hasbeen applied thereto. The coated paperthen apasses under the roller 38and on throu h other parts of the machine,-not shown, tof 0 dried orotherwise treated .and finished. 5

The equalizer rod is heldin position by the bar which forms a rightangle grooveor notch with the rear 'face'ofthe square tube 54.

If desired, the rod may be moved with reference to the paper and boxduring operation as suggested in the patentv to Mayer referred to above.

The equalizer rod ordinarily used is about three-sixteenths inch indiameter and is provided with an engaging or active surface havingconvolutions formedby a very fine thread or by tightly wound wire ofvery small diameter The diameter'of the wire or the size of the threadsdetermines the thickness of the layer of coating material remaining onthe paper as it passes from the equalizer rod. In making one type ofcarbon paper the diameter of the wire is about four thousandths of aninch, but if the diameter of the wire is smaller the thickness of thelayer of coating material will be less; and if larger, the thickness ofthe coating will be greater.

It is of the utmost importance that the bearing surface of the equalizerrod should not be worn down since any variation in depth of the spacesbetween turns of the wire or thread will result in' variations in thethickness of the layer of coating. lVhen such wearing down of theconvolutions occurs the thickness of the coating is vdecreased. Inpractice'it is found that the portions of the material coatedin theearly stages is thicker than that which is applied when the rod is worndown.

Ordinarily, the wire used to form the convolutions is made of iron orsteel and is soon worn down not only by the passage of the paper overthe wire but also by reason of friction between the. rod and the troughformed by the square box 54 and the bar 55, in which the rod issupported. The small spaces between the convolutions of wire then becomecomparatively shallow sothat the layer of coating becomes thinner as theoperation continues.

In practice this variation is so pronounced that the equalizer rod hasto be removed after running about 200 to 250 reams of paper. The wornrod may be used for producing coated products having a thinner layer ofcoating material but a new rod must be substituted in order to continueto produce paper coated to the same thickness as that already run.

In the present invention this difiiculty is overcome and a productproduced having a layer of substantially uniform thickness throughoutthe length of the material.

This is accomplished" by providing the equalizer rod with a coating ofhard Wearresisting material This is preferably efl'ected by depositing acoating of chromium upon the wire or over the thre'adsof the rod, byelectro-plating. The chromium plating is particularly effective whenapplied to a completed wire-wound rod, that is, after the wire has beenapplied thereto and while held tightly in place. Figure 2 of thedrawings illustrates an enlarged portion of such a rod showing the rod56 to which the wire 60 is applied, the wire being provided with acoating 62 of chromium.

The plated chromium surface is the only portion of the rod which isengaged by the paper. The hard bearing surface thus provided preventswearing away of the fine wire or threads so that the product produced bythe use of the present invention is of umform quality over long periodsof operation. It

.tween adjacent turns of the wire are partially filled with the platingmaterial so. as to provide a bond between the same, thus increasing thestrength and wearing characteristics of the rod. Furthermore, theplating seems to be deposited most heavily on the outermost part of thewires or threads, with the result that the coating material is spread bythe rod thicker and more evenly than by a similar unplated rod when awire winding is used, the spaces between the turns of the wire or at thebase of the threads are rounded out by the'plating material.

The invention is not limited to its use in connection with machines suchas that described above but may be used with other coating machines ormechanism for applying an even coating of material to webs or sheets ofmaterial. Therefore it is not intended to limit the invention to theparticular combination of parts shown and described except as defined bythe claims.

I have used in theaccompanying claims the word helical to describe athread running around the surface of the rod always at an oblique angleto a plane normal to the axis of the rod. It is tobe understood that theuse of the Word helical is in no sense intended to limit the shape ofthe rod to that of a geometrical cylinder, and it also is to beunderstood that the threads may with somewhat less advantage lie inplanes'normal to the axis of the rod.

What is claimed as new is 1. An equalizer rod for use in coatingmachines, whieh is. provided about its circumference with fineconvolutions; formed of fine wire closely and tightly wound,characterized by the fact that the rod has a coating of chromium oversaid wire winding which is continuous in a direction longitudinal of therod.

f 2. An equalizer rod for use in coating machines whichcomprises a rodwound with a nne wire, the convolutions of which are substantiallytouching one another and having a coating of an abrasion-resisting metalcontinuous longitudinally of the rod.

' 3. A method'of making an equalizer rod for use in coating machineswhich comprises winding :1 fine wire over the surface of a rod andthereafter coating the re thus formed. with a material resistant to crrosion and abrasion.

Signed at New York, New York, this 29th day of March, 1929.

JACOB A. L. MQLLER.

